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  1. #1
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    Taking vrv superheat and subcooling temperatures.



    Hi guys
    how do you take these Reading on a vrv system?
    Many thanks



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    Re: Taking vrv superheat and subcooling temperatures.

    Quote Originally Posted by alec View Post
    Hi guys
    how do you take these Reading on a vrv system?
    Many thanks
    Service Checker

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    Re: Taking vrv superheat and subcooling temperatures.

    Quote Originally Posted by multisync View Post
    Service Checker
    How do I get one if these?

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    Re: Taking vrv superheat and subcooling temperatures.

    Quote Originally Posted by alec View Post
    How do I get one if these?
    D.UK 1200 quid :-)

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    Re: Taking vrv superheat and subcooling temperatures.

    I'll get two... Lol

    Is there no way then? As a service checker won't work on anything else than Daikin will it? To check correct cooling can you only use liquid/vapour Reading in gauges and air ok/off?
    Many thanks

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    Re: Taking vrv superheat and subcooling temperatures.

    Quote Originally Posted by alec View Post
    I'll get two... Lol

    Is there no way then? As a service checker won't work on anything else than Daikin will it? To check correct cooling can you only use liquid/vapour Reading in gauges and air ok/off?
    Many thanks
    To check correct cooling you only need to set system in test mode and measure air flow and its temperature and humidity before and after every coil. Than you could calculate actual capacity and compare that with declared capacity.
    Last edited by nike123; 02-07-2010 at 09:08 AM.

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    Re: Taking vrv superheat and subcooling temperatures.

    You can measure superheat and subcooling on a VRV but it depends on what information you need.

    You're unlikely to see steady sub cooling until the VRV is running at its maximum ( TEST mode as Nike says ) and has been running long enough for all the expansion devices to settle. This is the best time to also check individual or total super heat and establishing a reasonable approximation of the charge state.

    So you can measure with gauges and temps. but you must be sure that the VRV is in good working order or the above doesn't count for a lot.

    Manufacturers service checkers are by far the easiest, quickest and (due to the fact that the sensor readings are updated all the time) generally more accuratley.
    Quidvis Recte Factum Quamvis Humile Praeclarum.

    Latine dictum, sit altum videtur.

    Si hoc comprehendere potes, gratias age magistro Latinae.

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    Re: Taking vrv superheat and subcooling temperatures.

    where would you take the readings? could you take it for every evap coil? or just last one?

    would you measure liquid line coming out of the condesner on gauges then take temp reading at the unit?

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    Re: Taking vrv superheat and subcooling temperatures.

    with vrv systems having expansion devices on every evap, you would need to check every system. most manufacturers have away of interrogating every system to monitor the superheats and control the expansion devices to make sure every system is running at maximum efficiency. also most manufacturers have a way for the service engineer to see these readings, sometimes this involves buying an expensive piece of diagnostic equipment, sometimes through the remote controller, dip switches etc it depends on the manufacturer.

  10. #10
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    Re: Taking vrv superheat and subcooling temperatures.

    how to calculate subcooling.

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    Re: Taking vrv superheat and subcooling temperatures.

    Hi:
    I'm new to the forum. I don't know how to post. could you plaes help?
    Sonic

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    Re: Taking vrv superheat and subcooling temperatures.

    Quote Originally Posted by sonic View Post
    Hi:
    I'm new to the forum. I don't know how to post. could you plaes help?
    Sonic
    http://www.refrigeration-engineer.com/forums/faq.php

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    Re: Taking vrv superheat and subcooling temperatures.

    Many Thanks 4 help

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    Re: Taking vrv superheat and subcooling temperatures.

    On Daikin VRV you can check on the local controller -Controller Sensor/Air On Sensor/Liquid Pipe inlet Sensor/gas pipe Sensor.
    You can then measure superheats from there.

    As Mulitsync says the best idea is to get a service checker.

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    Re: Taking vrv superheat and subcooling temperatures.

    Wozza can you explain how to get those values from the local controller please. In what sequence do i press the buttons ect, I seen an engineer check what the expansion valves were doing via the controller once on a sanyo vrf but he didn't wanna show me how to do it for some reason. cheers

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    Re: Taking vrv superheat and subcooling temperatures.

    Quote Originally Posted by Improver View Post
    Wozza can you explain how to get those values from the local controller please. In what sequence do i press the buttons ect, I seen an engineer check what the expansion valves were doing via the controller once on a sanyo vrf but he didn't wanna show me how to do it for some reason. cheers
    Hello Mate,

    Press and hold the Test button for 5 seconds and 00 or 10 will appear (depending on if it has a central controller), then press and hold test again to access the 40 menu press temperature up to 41 and on the left hand side you will see the temps, timer up and down to scroll through the sensors, 00=RC Sensor 01=RA Sensor 02 and 03 are the coil sensors, can't remember off hand which one is which.

    Just press test once to return to the default screen, If you download any VRV service manual from the Daikin extranet it will also be in there, for future reference you can obtain these values on the Mitsi from the outdoor board.

    Got to agree with Multi about the service checker, especially if you are working in buildings with access issues.

    Cheers
    Tutto il Mondo e un Paese

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    Re: Taking vrv superheat and subcooling temperatures.

    muchas gracias el padre

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    Re: Taking vrv superheat and subcooling temperatures.

    02 is coil sensor
    03 is gas sensor( hot gas in heating,suction in cooling)

    Sorry for late reply

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